Steel retainer



w. A. SMITH. SR

STEEL RETAINER Filed A11 4. 1937 Dec. 5, 1939.

I lN VENTOR WWII/01214452311553! BY i JHIS ATTORNEY.

Patented Dec. 5, 1939 UNITED STAT ATE T OFFICE STEEL RETAINER William A.Smith, Sr.,

Athens, Pa., assignor to Application August i,

2 Claims.

This invention relates to rock drills, and more particularly to a steelretainer for rock drills of the hammer type in which the workingimplement and the hammer piston actuating it are capable ofreciprocating independently of each other.

One object of the invention is to retain the working implement in therock drill.

Another object is to cushion the movement of the retainer with respectto the member supporting it, and

Another object is to assure a simplified and rugged retaining devicewhich is reliable in operation and may be conveniently manipulated.

Other objects will be in part obvious and in part pointed outhereinafter.

In the drawing accompanying this specification and in which similarreference numerals refer to similar parts,

Figure 1 is an elevation, partly in section, of the retainer and thefront end of a rock drill to which the retainer is attached,

Figure 2 is a transverse view taken through Figure l on the line 22, and

Figure 3 is a perspective view of the retainer.

Referring more particularly to the drawing, the retainer constructed inaccordance with the practiceof the invention and designated 29 is shownattached to the front end of a rock drill 2! for retaining a workingimplement 22 therein.

The rock drill selected for the purpose of illustration comprises acylinder 23 .and a front head 24 which is centralized with respect tothe cylinder 23 by a front cylinder washer 25 interposed between the twoand having portions extending into their adjacent ends. The frontcylinder washer 25, moreover, serves as a guide for an anvil block 26which transmits the blows of a hammer piston 2i, reciprocable in thecylinder 23, to the working implement 22.

Within the front head is a chuck 28 having a bore 2% to receive andconform with the shank 39 of the working implement. The chuck 28 may beaffixed to the front head 26 in any'well known manner and its front end31 serves as an abutment for a collar 32 at the juncture of the bodyportion of the working implement and the shank 3B.

In accordance with the practice of the invention, the front head 2 isprovided, near its front end, with a pair of laterally extending lugs 33which are arranged in parallelism with respect to each other andsuitably spaced to receive therebetween a head 34 forming, in thepresent instance, the rearmost terminal of the retainer 26).

1937, Serial No. 157,279

The head 3 is of substantially the same width as the space between thelugs 33, having only a slide fit between the lugs, and has an aperture3% to receive a pivot pin 36 which also extends through. coaxiallyaligned apertures 31 in the lugs 33.

Depending from the head 34 is a loop 38 consisting of portions 39 and itwhich are angularly arranged with respect to each other and in such wisethat when the retainer 26 occupies its retaining position the portion Milies perpendicular to the working implement 22, which it partlyencircles.

' The retainer 26 is in the form of a loop and its interior an oblongslot 4| extending through the portion ii; and partly through the portion39 and opens into an aperture 52 which is of sufiiciently largerdiameter than the collar 32 to permit the latter to pass readilytherethrough. The slot 4! is only of slightly smaller width than thediameter or maximum cross-dimension of the working implement in order toavoid contact between the two. Preferably, the surface of the retainerwhich is intended to engage the collar 32 is formed by the bottom 43 ofa depression 44 surrounding the slot 4|.

In order that the retainer 20 may be securely held in either theretaining or releasing position the peripheral surface" of the head 34is provided with diverging inclined surfaces 45 and 46 adapted to seatagainst a surface 47 on the periphery of the front head 24 and lyingbetween the lugs 33. The surface 45 serves to hold the retainer in theretaining position and lies perpendicular to the portion iL-while thesurface 46 bears a similar relation to the portion 39 of the retainerand engages the surface 41 for holding the retainer in the releasingposition, as indicated by dot and dash lines in Figure 1.

To the end that the retainer and the portion of the rock drill wherewithit is associated. may be protected against the destructive effectsaccompanying or following the impact of the collar 32 against theretainer, the ends of the pivot pin lying exteriorly of the retainer andextending through the apertures 31 are journalled in flexible,preferably rubber, sleeves 48 seated in the apertures 31. The walls ofthe sleeves 48 are of suitable thickness so that they will exert acushioning effect both upon the delivery of a blow against the retainerand during the subsequent rebound of the retainer.

In order to prevent the rubber of the sleeves 48 from being squeezed outof the apertures 31 plates or washers 49 are disposed upon the pivot pin36 and held firmly seated against the outer surfaces of the lugs 33 bycotter pins 50 arranged in the pin 36.

In practice, the sleeves 48 will yield readily to any force or shockapplied to the retainer 20 and will act to immediately restore theretainer to the position which it occupied prior to the delivery of suchforce thereto. The sleeves, moreover, supply the yieldable pressureessential to maintain the surfaces 45 or 46, depending upon whether theretainer is'in the retaining or releasing positions, against the surface41 on the front head. i

The operation of the device is as follows: Whe ever it is desired tochange working implements 22, the retainer is rocked to ,the'positionillustrated by dot and dash lines Where it is held by the pressure ofthe rubber sleeves which will then maintain the surface 46 firmly seatedagainst the surface M. With the retainer thus arranged the aperture 42will be in registry with the bore 29. The working implement 22 may thenbe withdrawn from the chuck since, as has been previously explained, thecollar 32 will then pass readily through the aperture 42. 1

After another working implement has been placed in the chuck 36 theretainer is again rocked to the retaining position where it willbe heldby the sleeves 48 which supply the force required to maintain thesurface 45 firmly seated against the surface 41. If, during thesubsequent operation of the rock drill the working implement isprojected sharply forwardly, as frequently happens when insufiicientresistance acts against the end of the working implement to maintain thetoner 32 against the chuck 2a, the collar 32 .will strike the portion 40of the retainer and in this way the working implement will be preventedfrom being projected from the rock drill.

I claim:

1. A steel retainer for a rock drill comprising, in combination with afront head and a collared working implement, a pair of lugs on the fronthead having coaXially aligned apertures, a retainer cooperating with thecollar of the imple-' ment to retain the implement in the front head,

a pivot in the apertures extending through the retainer, seatingsurfaces on the retainer to engage the front head for holding theretainer in retaining and releasing positions, and resilient sleeves inthe apertures to serve as bearings for the pivot and to press theseating surfaces into engagement with the front head.

2. A steel retainer for a rock drill comprising, in combination with afront head and a collared working implement, a pair of lugs on the frontheadhaving coaxially aligned apertures, a retainer cooperating with thecollar of the implement to retain the implement in the front head, ahead lying between the lugs and forming a 010- sure for the inner endsof the apertures, a pivot pin in the heaolv and the apertures, seatingsurfaces on the head to engage the front head for holding the retainerin retaining and releasing positions, rubber sleeves in the apertures toserve as bearings for the ends of the pivot pin and to press the seatingsurfaces against the front head, and closures for the outer ends of theapertures.

WILLIAM A. SMITH, SR.

